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Grand Central M4 Express discconnecting and reconnecting
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Grand Central M4 Express discconnecting and reconnecting

by ptremblett on Tue Sep 08, 2020 5:19 pm

I purchased an M4 to experiment with the size of Python program I can run on it. When I plug it into a USB port, the behavior is very different from what I experienced with the Metro. It shows up in the Mac OS finder as CIRCUITPY and I se it mounted as /Volumes/CIRCUITPY. It then pops up a dialog saying disk was not ejected properly. If I unmount it in Finder, after a few seconds it reappears along with the popup dialog. If I double-click the reset button, GCM4BOOT shows up in Finder and in the /Volumes directory and now the popup appears indicating that GCM4BOOT was not ejected properly. I am able to connect using the screen command but the interpreter exits after a few seconds. I have included the screen I see below. I am assuming the reason for today's date is I *think* I uploaded a newly built circuitpython. Can anybody shed some light on what might be going on? The behavior is so different from the behavior of the Metro board, which I have already determined can not accommodate the code I would like to run, that I am tempted to just trash the GC and move on.

This is what I see when I connect using screen:

Auto-reload is on. Simply save files over USB to run them or enter REPL to disable.

Press any key to enter the REPL. Use CTRL-D to reload.
Adafruit CircuitPython 6.0.0-alpha.2-359-gdc36a2c0b on 2020-09-08; Adafruit Grand Central M4 Express with samd51p20
>>>

ptremblett
 
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Re: Grand Central M4 Express discconnecting and reconnecting

by adafruit_support_carter on Tue Sep 08, 2020 6:39 pm

What is the other Metro board you were using? It sounds like this is mainly the difference between Arduino and CircuitPython. You can use either with the Grand Central M4.

You currently have CircuitPython loaded. See here for general info:
https://learn.adafruit.com/welcome-to-circuitpython

CIRCUITPY is the folder you see when CircuitPython is running.
GCM4BOOT is the folder you see when the bootloader is running.
You can probably generally ignore the warnings about proper ejection.
What you are seeing in the screen session is the REPL interface.

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Re: Grand Central M4 Express discconnecting and reconnecting

by ptremblett on Tue Sep 08, 2020 9:40 pm

The other board I was using was the Metro and on hat board the demo code was visible. I assumed I was seeing CircuitPython based on: Adafruit CircuitPython 6.0.0-alpha.2-359-gdc36a2c0b

So what is the explanation for the board disconnecting itself and remounting itself every minute or so forever?

ptremblett
 
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Re: Grand Central M4 Express discconnecting and reconnecting

by ptremblett on Tue Sep 08, 2020 11:41 pm

When I examined INFO_UF2.TXT,, I saw that the version of the BootLoader was antiquated so I updated it and the behavior of he board stabilized. It no longer went into an endless loop of connecting and disconnecting. I then re-installed CircuitPython from a version I had just built, uploaded my Python code, and renamed my file that contained the startup code to main.py, Now when I do a soft reset from the screen window, it attempts to run my code. It complains because I am using extended iterative unpacking so now it looks like its a matter of re-writing those portions of the code that CircuitPython doe snot appear to support.

Bottom line - the problem I was experiencing has been solved.

ptremblett
 
Posts: 10
Joined: Fri Jun 12, 2020 12:03 am

Please be positive and constructive with your questions and comments.